This is a major milestone:

But to be viable, fusion power plants would have to produce more energy than they consume, which has proven elusive.

Now, a breakthrough by scientists at the National Ignition Facility (NIF) could boost hopes of scaling up fusion.

NIF, based at Livermore in California, uses 192 beams from the world’s most powerful laser to heat and compress a small pellet of hydrogen fuel to the point where nuclear fusion reactions take place.

This is known as “inertial confinement”. Basically heat and pressure is created because the concentrated lasers heat up the pellet so rapidly that it creates intense heats and pressures.

Note that “Break Even” does have a qualifier though:

This is a step short of the lab’s stated goal of “ignition”, where nuclear fusion generates as much energy as the lasers supply. This is because known “inefficiencies” in different parts of the system mean not all the energy supplied through the laser is delivered to the fuel.

But the latest achievement has been described as the single most meaningful step for fusion in recent years, and demonstrates NIF is well on its way towards the coveted target of ignition and self-sustaining fusion.

Interestingly, inertial confinement, which has gotten far less funding and attention than magnetic confinement, most notably the Tokomak and Stellerator configurations, but they have not progressed as far.

Inertial containment is a lot simpler, both from a physics and an engineering standpoint, but making it economically viable appears appears rather more difficult than for magnetic confinement, because inertial confinement is by its nature an intermittent process.